[j-nsp] How to protect the firewall

[james list]

Hi experts,
I've a customer which experienced a big trouble since one of the server
system engineer in the company has assigned to a test server the same ip
address of the firewall cluster.

They do not have networking resources and got time to understand the issue.

My question: is there a way to protect the firewall ip addressing from
other machines in lan which could send gratuitous arp with these addresses ?

The ip addressing is static, no dhcp assignment on the server.

Any idea/help is appreciated.

Cheers
James